This invention generally relates to the field of cleansers, cleansing products, or processes of making cleansers.
Liposomes or lipid vesicles are closed bilayer structures. The bilayer structure includes two membranes. Each membrane has a polar end and a nonpolar end. The membranes in the bilayer may either have their polar ends or nonpolar ends in an abutting relation. There are many uses for these structures, such as adjuvants and carriers for the transportation of encapsulated drugs or biologically-active substances.
Often, a lipid vesicle is classified into three groups by size and structure: large unilamellar vesicle (hereinafter may be referred to as xe2x80x9cLUVxe2x80x9d), small unilamellar vesicle (hereinafter may be referred to as xe2x80x9cSUVxe2x80x9d), and multilamellar vesicle (hereinafter may be referred to as xe2x80x9cMLVxe2x80x9d). LUV may have a diameter greater than about 1 micron and may be formed of a lipid bilayer surrounding a large, unstructured aqueous phase. SUV may be similar in structure to the LUV except their diameters may be less than about 0.2 micron. A MLV may have an onion-like structure having a series of substantially spherical shells formed of lipid bilayers interspersed with aqueous layers. LUV, SUV, and MLV structures may be manufactured by various mechanisms, including those described in xe2x80x9cLIPOSOMESxe2x80x94Potential for Commercial Applicationxe2x80x9d, by Dr. Norman D. Weiner, presented at the Emulsion-Suspension Technology Conference, Oct. 20-23, 1997, at New Brunswick, N.J.
A fourth type of lipid vesicle, which may be particularly well suited for transport of either lipids or aqueous materials, is a paucilamellar vesicle (hereinafter may be referred to as xe2x80x9cPLVxe2x80x9d). This type of vesicle may have an external structure of about two to about eight peripheral lipid bilayers with a large, unstructured aqueous center. Liquid droplets, such as oil, may be suspended in the center, leading to very high uptake of non-aqueous or lipophilic materials. The paucilamellar vesicle may range from about 2 to about 15 micron in diameter. Methods of making PLV are described in U.S. Pat. No. 4,911,928 to Wallach, issued Mar. 27, 1990.
Besides being used as medical delivery devices, liposomes, particularly PLVs, may be used as cleansers. These cleansers may be used to remove oil and/or dirt from surfaces, such as skin. Desirably, these liposomes encapsulate a non-aqueous solution and are applied to a surface. Agitation, such as rubbing ones hands, may break the liposomes freeing the non-aqueous solution. Afterwards, the liposomes may reform encapsulating the oil and dirt. The freed non-aqueous solution may aid in removing the liposomes from the surface.
Unfortunately, these cleansers suffer several disadvantages. Although liposomes may be used as cleansers for various organic contaminates, they may not be adequate for some contaminates, such as those present in the paint and printing industry. Furthermore, liposomes may benefit the skin by replacing natural oils lost during the cleansing process. Removing the liposomes after cleansing probably deprives the skin of this benefit. Also, the conventional wisdom is that no more than 40 weight percent cleansing solvent may be loaded into the premade PLVs. This solvent loading ceiling may limit the amount of added solvent to the liposomes, thereby impeding subsequent cleaning. Moreover, it is believed that as the PLV ages, the amount of solvent loaded into the PLV will be reduced. Currently, it is recommended loading PLVs with solvent within a week of the PLVs manufacture date, or ideally, during the PLV manufacturing process. This time constraint may limit manufacturing flexibility, and also result in waste of materials.
Accordingly, a liposome cleanser that increases use and manufacture versatility, acts as skin moisturizer, and improves manufacturing efficiencies, will improve over conventional liposome cleansers.
As used herein, the term xe2x80x9cincludexe2x80x9d refers to a part or parts of a whole, but does not exclude other parts. The term xe2x80x9cincludexe2x80x9d may have the same meaning and may be interchanged with the terms xe2x80x9ccomprisexe2x80x9d and xe2x80x9chavexe2x80x9d.
As used herein, the term xe2x80x9ccleanserxe2x80x9d refers to a substance, such as a liquid, suspension, or powder, used to free foreign or extraneous matter. Cleanser examples include soaps, detergents, solvents, and liposomal cleansers. A liposomal cleanser may include a liposome having an aqueous center that entrains a solvent.
As used herein, the term xe2x80x9ccarrierxe2x80x9d refers to a liquid substance that supports another substance. In addition, a carrier may have other properties, such as cleaning properties, and particularly, may act as a surfactant.
As used herein, the term xe2x80x9ccleansing productxe2x80x9d refers to a product having a cleanser and a carrier.
As used herein, the term xe2x80x9cliposomexe2x80x9d means a closed lamellar vesicle that forms in aqueous suspensions of various lipids or lipid mixtures. The term xe2x80x9cliposomexe2x80x9d may have the same meaning and may be interchanged with the term xe2x80x9clipid vesiclexe2x80x9d. Liposome examples include large unilamellar vesicles, multilamellar vesicles, paucilamellar vesicles, small unilamellar vesicles, reverse phase evaporation vesicles, French press vesicles, and ether injection vesicles. Products incorporating liposomes include adjuvants, drug carriers, and cleansers. The following references disclose methods and/or apparatuses for manufacturing liposomes: xe2x80x9cLIPOSOMESxe2x80x94Potential for Commercial Applicationxe2x80x9d, by Dr. Norman D. Weiner, presented at the Emulsion-Suspension Technology Conference, Oct. 20-23, 1997, at New Brunswick, N.J.; U.S. Pat. No. 4,911,928 to Wallach, issued Mar. 27, 1990; U.S. Pat. No. 4,855,090 to Wallach, issued Aug. 8, 1989; and U.S. Pat. No. 4,895,452 to Yiournas et al., issued Jan. 23, 1990.
As used herein, the term xe2x80x9cvesiclexe2x80x9d means a small, thin-walled bladderlike cavity, typically filled with fluid.
As used herein, the term xe2x80x9cmanufacturedxe2x80x9d means to have made a material functional for its intended purpose. Manufactured does not mean any subsequent commercial steps, such as packaging or bottling.
As used herein, the term xe2x80x9cisoprenoidxe2x80x9d means substances that include isoprene units of the chemical formula C5H8. Isoprenoids include terpenes, sesquiterpenes, diterpenes, and triterpenes. Isoprenoids may be extracted from plants such as cloves, roses, lavender, citronella, eucalyptus, peppermint, camphor, sandalwood, cedar, and turpentine.
As used herein, the term xe2x80x9cesterxe2x80x9d refers to a substance formed by the bonding of an alcohol and an organic acid. Ester examples include animal fats, such as stearic acid, and fragrances, such as isopentyl acetate or octyl acetate.
As used herein, the term xe2x80x9cdibasic esterxe2x80x9d refers to an ester containing two hydrogens that may be replaced by a monovalent metal or radical. Examples of dibasic esters include dimethyl glutarate, dimethyl adipate, and dimethyl succinate.
As used herein, the term xe2x80x9csolventxe2x80x9d refers to a material that dissolves another substance while not changing its physical state. The solvent does not have to be the majority component of the resultant solution. Examples of solvents include synthetic and natural hydrocarbons. Synthetic and natural hydrocarbons may include dibasic esters, terpenes, mixtures of isoprenoid and mineral oil substances, naphthas, glycol ethers, parrafinic and isoparrafinic hydrocarbons, aromatic hydrocarbons, petroleum distillates, vegetable oils, animal oils, organic halides, halogenated solvents, and alcohols. Terpenes may include d-limonene and the dibasic esters may include dimethyl glutarate, dimethyl adipate, and dimethyl succinate.
As used herein, the term xe2x80x9clarge unilamellar vesiclexe2x80x9d refers to a lipid bilayer surrounding a large, unstructured aqueous phase and having a diameter greater than about 1 micron. The term xe2x80x9clarge unilamellar vesiclexe2x80x9d may be abbreviated as xe2x80x9cLUVxe2x80x9d and a plurality of large unilamellar vesicles may be abbreviated as xe2x80x9cLUVsxe2x80x9d. FIG. 1 is a schematic illustration of an exemplary LUV 10. The LUV 10 may include an amorphous center 20 and a bilayer 30.
As used herein, the term xe2x80x9csmall unilamellar vesiclexe2x80x9d refers to a lipid bilayer surrounding a unstructured aqueous phase and having a diameter less than about 0.2 micron. The term xe2x80x9csmall unilamellar vesiclexe2x80x9d may be abbreviated as xe2x80x9cSUVxe2x80x9d and a plurality of small unilamellar vesicles may be abbreviated as xe2x80x9cSUVsxe2x80x9d. FIG. 2 is a schematic illustration of an exemplary SUV 100. The SUV 100 may include an amorphous center 120 and a bilayer 130.
As used herein, the term xe2x80x9cmultilamellar vesiclexe2x80x9d refers to an onion-like structure having a series of substantially spherical shells formed of lipid bilayers interspersed with aqueous layers and a diameter from about 0.05 to about 10.0 micron. The term xe2x80x9cmultilamellar vesiclexe2x80x9d may be abbreviated as xe2x80x9cMLVxe2x80x9d and a plurality of multilamellar vesicles may be abbreviated as xe2x80x9cMLVsxe2x80x9d. FIG. 3 is a schematic illustration of an exemplary MLV 200. The MLV 200 may include an amorphous center 220 and eight bilayers 230-237.
As used herein, the term xe2x80x9cpaucilamellar vesiclexe2x80x9d refers to an external structure having about two to about eight peripheral lipid bilayers with a large, unstructured aqueous center and a diameter from about 2 to about 15 micron. The term xe2x80x9cpaucilamellar vesiclexe2x80x9d may be abbreviated as xe2x80x9cPLVxe2x80x9d and a plurality of paucilamellar vesicles may be abbreviated as xe2x80x9cPLVsxe2x80x9d. FIG. 4 is a schematic illustration of an exemplary PLV 300. The PLV 300 may include an amorphous center 320 and three bilayers 330-332. Generally, PLVs have a larger center than MLVs, permitting PLVs to encapsulate more drugs or solvents.
As used herein, the term xe2x80x9cmeans for encapsulatingxe2x80x9d refers to substance encapsulating a solvent. Means for encapsulating examples include liposomes and gelatin beads.
As used herein, the term xe2x80x9cweight percentxe2x80x9d refers to the ratio of the weight of a particular component to the total weight of the whole item multiplied by 100. As an example, 40 grams of a solvent loaded into 60 grams of a liposome may be expressed as 40 weight percent solvent.
The problems and needs described above are addressed by the present invention, which provides a cleanser including a liposome and greater than about 40 weight percent of a solvent. The liposome may be loaded with the solvent more than about 7 days after the manufacture of the liposome. The solvent may be an isoprenoid or ester solvent. Furthermore, the solvent may be d-limonene or a dibasic ester. In addition, the liposome may be selected from the group consisting of large unilamellar vesicles, multilamellar vesicles, paucilamellar vesicles, and small unilamellar vesicles. Desirably, the liposome is a paucilamellar vesicle. Desirably, the cleanser may have a solvent weight percent greater than about 60. More desirably, the cleanser may have a weight percent of solvent greater than about 80. Moreover, the solvent may be about a 1:1 weight ratio of d-limonene and dibasic ester.
In addition, the present invention includes a process of making a cleanser. The process may include the steps of providing a liposome, providing a solvent, and loading the liposome so the liposome contains greater than about 40 weight percent of the solvent. The solvent may be an isoprenoid or ester solvent. Moreover, the solvent may be d-limonene or a dibasic ester. Furthermore, the liposome may be selected from the group consisting of large unilamellar vesicles, multilamellar vesicles, paucilamellar vesicles, and small unilamellar vesicles. Desirably, the liposome is a paucilamellar vesicle. Desirably, the solvent weight percent may be greater than about 60. More desirably, the solvent weight percent may be greater than about 80.
Moreover, the present invention includes another process for making a cleanser. The process may include the steps of providing a liposome, providing a solvent, and loading the liposome with the solvent. The loading may be carried out more than about 7 days after the manufacture of the liposome. In addition, the loading may be carried out more than about 21 days after the manufacture of the liposome. Likewise, the loading may be carried out more than about 60 days after the manufacture of the liposome. Similarly, the loading may be carried out more than about 90 days after the manufacture of the liposome.
Furthermore, the present invention includes a cleanser having a means for encapsulating and greater than about 40 weight percent of a solvent. The means for encapsulating may be a liposome. Desirably, the liposome is selected from the group consisting of large unilamellar vesicles, multilamellar vesicles, paucilamellar vesicles, and small unilamellar vesicles. The solvent may be d-limonene or a dibasic ester.
Also, the present invention includes a cleanser having a paucilamellar vesicle and greater than about 40 weight percent of a dibasic ester solvent. The paucilamellar vesicle may be loaded with the solvent more than about 90 days after the manufacture of the paucilamellar vesicle.
Moreover, the present invention includes a cleanser made by including a liposome and greater than about 40 weight percent of a solvent. The liposome may be loaded with the solvent more than about 7 days after the manufacture of the liposome.
Furthermore, the present invention includes a cleansing product including a cleanser having a liposome and a carrier. The liposome may be loaded with greater than about 40 weight percent of a solvent more than about 7 days after the manufacture of the liposome.
Likewise, the present invention includes a cleanser including a means for encapsulating and a solvent where the cleanser has a cleaning percent for oil based printers ink greater than about 50 percent.